The official iPhone, iPad, and iPod touch app for the Tumblr social network has been unavailable since November 16th. This is due to the discovery of illicit content pertaining to the exploitation of children during a routine content audit.
The social network put out a statement on the matter on its official Help Center page for the app's current lack of availability on iOS:
We’re committed to helping build a safe online environment for all users, and we have a zero tolerance policy when it comes to media featuring child sexual exploitation and abuse. As this is an industry-wide problem, we work collaboratively with our industry peers and partners like NCMEC to actively monitor content uploaded to the platform. Every image uploaded to Tumblr is scanned against an industry database of known child sexual abuse material, and images that are detected never reach the platform. A routine audit discovered content on our platform that had not yet been included in the industry database. We immediately removed this content. Content safeguards are a challenging aspect of operating scaled platforms. We’re continuously assessing further steps we can take to improve and there is no higher priority for our team.
Since this discovery and removal of the Tumblr app for iOS, the official Help Center page has updated four times, all stating very similarly that their development team is continuing to work on restoring the app's presence on the App Store.